What is in this article?:
• Weather conditions in 2010 were very hot and dry, ideal conditions for the development of Southern corn rust.
• The arsenal of fungicides available for foliar diseases in corn continues to grow and now includes Tilt and other propiconazole products, tebuconazole products, Stratego, Stratego YLD, Headline, Headline AMP, Quadris, Quilt, Quilt Xcel, Evito, and Evito T.
Depends on yield expectations
Whether or not you should spray fungicides on corn depends upon your yield expectations, growing conditions, and the disease potential based on Sentinel plots, says Kemerait. “But what I can tell you is after 2010, an aggressive year, I feel much more confident about those early first-tassel applications. It’s not a hard and fast recommendation, there are other things to consider, but it worked.”
For a long time, says Kemerait, Extension specialists said that nematodes didn’t matter in corn because nematicides were so expensive compared to the price of corn. “We now see that managing nematodes with a product like Telone can buy you 25 bushels per acre at least. But Telone isn’t the only product available.In addition to Telone II, growers will have Counter 15G, Avicta Complete Corn, and Poncho/Votivo for consideration to use for management of nematodes in their corn fields.
“We know Telone and Counter are good products, but what about Avicta and Poncho/Votivo? Evicta is a seed treatment that contains a nematicide. Poncho/Votivo is not a nematicide, it’s a biological product. Both products do have a response in plant growth. It remains to be seen how well they do in tough nematode situations.”
Nematodes are taking a larger part of your yield than was first realized, says Kemerait. “Managing nematodes with a nematicide is going to be an appropriate action given the price of corn we now have and the management we use. If we put the inputs out there for 200-bushel corn, why let disease and nematodes take it?”
Aflatoxin is a major problem for corn and peanut production in Georgia, says Kemerait. Extreme heat and drought during the growing season, insect damage, and improper storage all can increase the risk of contamination with aflatoxin. High temperatures in 2010 certainly increased the risk for corn and peanut production, he says.
Syngenta Crop Protection has now acquired Afla-Guard, which is a non-toxigenic strain of Aspergillus flavus that can compete for colonization of the corn or peanuts with the native, toxigenic strains found in the field.
“Afla-Guard is applied at some point between the V10-V12 and R1 growth stages, or approximately 14 days prior to tasseling up to the onset of silking. The rate for application is 10 to 20 pounds per acre of product. The efficacy of Afla-Guard to minimize the levels of aflatoxin in corn in Georgia continues to be evaluated. The University of Georgia will develop detailed recommendations once a larger data set is available.”